Electrophysiologic mapping and cardiac ablation are two procedures which are typically performed inside of a beating heart. The mapping procedure is diagnostic and it is intended to reveal the location of regions of ectopic electrical activity within the heart which can give rise to tachyarrhythmias. Once an ectopic site has been localized, it is common to ablate tissue in that region of the heart to prevent conduction of electrical signals in that portion of the cardiac tissue. The ablation of tissue is a therapeutic and has been demonstrated to eliminate some tachyarrythmias.
Both brachial and femoral approaches to the interior of the heart are commonly used to introduce catheters. Approaching the heart through the thorax is not widely employed at the present time. Consequently the ability to quickly and reliably exchange instruments within the heart chamber is desirable. However it is difficult to exchange diagnostic and therapeutic catheters given current therapeutic approaches.